Derek Downey, a bee researcher at UC Davis, with one of his custom-built bee hives.

When almond bloom arrives early every year, more than 500,000 acres of almond trees in orchards across California must be pollinated. Equally predictably, thieves have begun targeted bee hives and their increasingly valuable contents.

In rural Yolo County near Sacramento, bee thief Viktor Zhdamirov was recently convicted of a felony for receiving stolen property. Sheriff’s deputies caught him with 80 stolen bee hives valued at more than $65,000. They were stolen in 2012.

More recently, bee bandits in Sacramento County stole $70,000 worth of hives from Roscoe Hall’s apiary near the town of Herald. They are still at large.

Like most beekeepers, Hall earns 80 percent of his income by renting bees to almond orchard owners. Honey production provides the rest of his income.

Bee thefts have not put much of a dent California’s multi-billion dollar almond industry. But beekeepers’ losses have increased as their hives become more valuable. Hive rents in recent years has soared from approximately $55 apiece to more than $200 in some areas.

As the number of almond trees grows, so does the demand for bees to pollinate them. A mysterious malady called Colony Collapse Disorder is emptying hives and exacerbating the shortage. With CCD, adult bees abandon hives and leave unhatched eggs and larvae behind.

Many factors are involved in CCD, experts say.

“Basically, it’s caused by stress,” explains Derek Downey, a beekeeper in Davis, Calif. “The pollinating bees are just stressed out. There are so many causes that CCD is perceived as mysterious.”

“We take their honey and most beekeepers substitute high fructose corn syrup to feed them. That’s the sweetening ingredient in most soda pop,” Downey said, adding that the poor diet puts bees at greater risks of disease.

The varroa mite is another factor. The parasite attaches itself to honey bees and passes viruses such as “deformed wing virus” to the hosts. A mite infestation can wipe out a hive.

During almond bloom, bees are trucked to California from apiaries across the country.

“When I parked in orchards this spring, I saw trucks from West Virginia, Florida, all over,” says Phil Hofland, a Dixon, Calif., beekeeper. Trucks were parked within a few feet of each other, and mite infestations and other diseases can spread like wildfire in those conditions, he said.

“There’s the potential for wiping out a lot of hives,” said Hofland.

While researchers seek a way to stop CCD, beekeepers are fighting back against thieves. Hofland says he is even considering installing Global Positioning System microchips on his hives.